


All In the Family

by Death_Rattle



Category: Harry Potter - J. K. Rowling
Genre: Blackcest (Harry Potter), Cousin Incest, F/M, Hate Sex, Incest, One Shot, Pre-Canon
Language: English
Status: Completed
Published: 2020-07-13
Updated: 2020-07-13
Packaged: 2021-03-05 01:13:54
Rating: Explicit
Warnings: Underage
Chapters: 1
Words: 1,794
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/25236007
Author URL: https://archiveofourown.org/users/Death_Rattle/pseuds/Death_Rattle
Summary: Toujours pur... a better reason than any to keep it in the family. —O/SOld. Re-written and cross-posted from FFN. Published 12.26.12
Relationships: Past Regulus Black/Bellatrix Black Lestrange, Sirius Black/Bellatrix Black Lestrange
Comments: 8
Kudos: 43





	All In the Family

Sirius Black sat alone in his bedroom late at night, frustrated, on edge... and it was all _her_ fault!

He supposed he'd been attracted to her ever since he was old enough to like girls, but back then it didn't matter, he was just a kid and it was just a harmless crush. Now, he was sixteen (almost seventeen) with raging hormones, and this was definitely not a harmless crush - it was lust. She consumed his every thought, it was madness, lust and madness.

Staying in the same house only made it worse. It was just for the holidays, his mother had said, but he was seriously beginning to doubt he could hold out until school resumed without doing something incredibly stupid.

He hadn't slept the night previous, nor would he tonight he reckoned. He couldn't shake the image of her in that scandalously low-cut dress she'd worn to dinner. He felt that familiar tightening in his pants... he had to have her, he just had to.

He had tried to find a new target, he'd really tried, but no amount of pretty, young Gryffindor girls could slake his lust. He just couldn't get her off his mind, even as those stupid, little school girls screamed his name while he fucked them like the worthless whores that they were. 

Merlin, he hated her, he hated her more than anyone... and the feeling was mutual, she'd made that quite clear.

His heart raced like a lab rat's when he heard the sound of footsteps just outside his bedroom door. He swore his heat skipped a beat altogether as the old wooden door opened with a _creeeeeaaaaak_.

"Your light is keeping me awake." Bellatrix said, flatly.

Sirius just sat there, stunned in silence for a moment. He could only stare. She had nothing on but a short, black nightdress (which just barely qualified as such).

"Are you feeling alright?" she asked, one dark eyebrow raised slightly.

"I-I'm fine!" he stammered, quickly standing up. "Something you need, Bella?"

"Hm, you don't look so good, cousin..." Bellatrix muttered, tactfully avoiding the question.

"I'm fine, really!"

Bella sighed and crossed her arms, making her cleavage even more pronounced.

Sirius's eyes widened and his face flushed, and he realized his pajama pants were beginning to feel uncomfortably tight.

"I don't believe you," she said, finally approaching him and closing the door behind her.

She leaned in close, so close he could feel her hot breath tickling his ear.

"Won't you tell me what's wrong, dear cousin?"

Sirius shivered involuntarily.

Bellatrix was laughing on the inside as she looked him over. Of course, she knew what was the matter. She was well into her twenties and married, she could tell what a man was thinking more often than not.

She had to admit she was rather curious about him, he was certainly handsome enough, and what's more he seemed to absolutely loathe her. It was oddly satisfying that someone who actively disliked her couldn't help but to be attracted to her.

Bellatrix nearly gasped aloud when Sirius grabbed her shoulders and pushed her against the wall with much more force than was needed. She tried her damndest not to show any emotion in her face, offering no more than a smug smile... which he hungrily kissed before she could even say a word, his tongue pushing past her lips and into her mouth, tasting menthol cigarettes and the tang of merlot.

Bellatrix was quick to shove him off her and slap him across the face, hard.

**Crack!**

He recoiled from the strike, almost losing his balance. It stung something awful and left his ears ringing, but somehow, it enticed him further. And well, he wasn't exactly surprised, he hadn't expected it to be easy after all.

"Sirius, you disgusting little boy! I'm your cousin!" Bellatrix hissed, feigning anger.

"Oh please, cousins fuck in this family, that's how me and my brother got here."

Once more, he forced his mouth onto hers and they were locked in a passionate kiss, his hands gently caressing her pale arms. His hips jutted forward, making her squeak as she felt his straining erection press into her. She bit down on his lower lip in response, grabbing a fist full of black, unruly hair and yanking forcefully, breaking the heated kiss.

"Is that what you think you're getting, a fuck?" she asked.

"Yes."

Shamelessly, he unbuttoned his pajama shirt which fell silently to the floor. Bellatrix took in his well-sculpted young body, liking what she saw despite herself. He took hold of her wrists, placing her hands on his naked skin and moving them over his defined abdominal muscles.

"I'm your cousin, Sirius" she persisted, though she knew it didn't matter.

"I don't care, Bella, and neither do you."

This time, he kissed her neck, gently at first, then experimenting with a bite here and there, making Bellatrix hiss with what very well could be pleasure.

"You're disgusting, bloody fucking disgusting!" she snarled.

"Is that what you said to my brother, too?" he replied, haughtily, his trembling fingers curling around the thin straps of her nightdress and tugging.

"What are you on about?"

"I know _all_ about you and Regulus. I know everything, how he had you moaning like a whore and begging him to do it harder - he said you couldn't walk right by the time he was done with you," Sirius mocked, pulling her nightdress down most of the way, the rest of the way it slid down on its own and pooled at her feet. "He told me you went back for more, too."

"Alright, so I let your brother fuck me," she said nonchalantly, as though they were discussing the weather. "He's much more handsome than you are, you know," she lied. Sirius didn't need to know she lied, though. "And I don't hate him, so there's that." She kicked the useless garment out of the way, and leaned back against the wall, smiling as her cousin admired her naked body.

"You don't hate me, Bella, not really."

"Oh, but I do."

Long, slender fingers danced between her plump breasts, slowly, then trailed down her abdomen. Bellatrix felt a knot form in her stomach and an ever so slight tingle between her legs. Who was she kidding? She wanted this.

The young man's ears delighted at the sounds Bella made as his mouth closed around one of her hard, pink nipples. He sucked eagerly, the tingling sensation becoming an ache. As if he knew what was happening, his hand slipped into her panties and his fingertips circled her clit, making moan loudly and grind against his hand.

He smiled. His fingers moved lower... she was already wet for him!

"Liar."

Bellatrix wanted to leave and give him nothing, that was what her mind wished for but her body wouldn't allow it. It pissed her off... he pissed her off, she hated him! Why did she want to fuck someone she hated anyhow? More to the point, why did she want to fuck a boy whose voice still cracked? Especially when that boy was her cousin!

_Wouldn't be the first time you fucked your cousin_

Well, that was a different story. Regulus adored her, and he'd practically begged her so she'd been more than happy to play with him... but why Sirius?

_Why Sirius?_

"Fuck me" she growled, against her better judgment.

After that, Sirius wasted no time. He took her by the waist and practically threw her onto the bed. Before she even had the chance to get her bearings, he climbed on top of her, his added weight making the mattress sink beneath them. Panting like a dog and practically shaking with anticipation, he undressed the rest of the way in what seemed a matter of seconds. Dark eyes watched intently as Bella inched off her panties, tortuously slow, then finally spread her legs for him. He settled in between her thighs, his lips meeting hers as the tip of his cock prodded her entrance.

With little warning, he thrust inside her. The tightness and pulsing heat was heavenly, Sirius let out a satisfied groan and buried his cock to the hilt, making Bella cry out, overwhelmed by the intertwinement of pleasure and pain setting seemingly every nerve in her body alight. He was larger than she thought he would be, he was stretching her and she was struggling to accommodate his impressive size. It felt amazing if a bit dizzying, having him so deep inside of her and taking her so roughly.

Sirius pounded into her without mercy. It was ecstasy, he felt close already... and she wasn't making it any easier on him, she moaned shamelessly as he rutted her like a whore, neither sparing any concern for whether or not someone would hear.

"Fuck!" she hissed, her fingernails raking his back. "Harder, harder! Fuck me like you mean it, cousin!"

Surprisingly strong hands took hold of her hips, using them as leverage so he could pound into her, harder, faster, deeper.

"Agh-haah! Yessss!" she exclaimed, arching her back and angling herself just so.

"Mm, Bella..." he groaned.

He was seconds away now, the pleasure was blinding, enough to override the sting of sharp nails tearing open his skin, tracing the bloodied trails over and again.

"Ahh!" Bellatrix screamed.

She was close as well, he could tell, he could hear her breaths quicken and feel her contracting around his cock. His hands closed around either side of her neck, hard but not quite hard enough to completely cut off her airflow. His brutal pace did not falter, not even for a second.

Her orgasm was indicated by a strangled half-scream and her pussy squeezing his shaft like a vice. She lost control, her eyes rolled back as she writhed beneath him, the look on her face worth one thousand words, sending him over the edge as well. His grip around her neck tightened as he came, inside of her, he didn't even think to pull out. Just when she began to panic, he let go, allowing her to breathe again.

The sound of heavy panting and the stink of sex soon filled the room. For the moment, the two cousins did nothing save for try to catch their breath.

Bellatrix was quick to shove Sirius off her and practically leap out of the rather comfortable bed.

"I'm not staying in here with you!" she huffed, before he could tell her he didn't even want her to.

"Good, I'm glad." he shot back, stretching languidly as though nothing had happened.

"Well, I'm glad you're glad." she replied, as she gathered her clothes and headed straight for the door.

"Bitch."

"Dick."

And with that, Bella left, slamming the door behind her.


End file.
